Examining the associations between maternal blood, umbilical cord blood arsenic

Project Summary

Chronic human exposure to inorganic arsenic (InAs) in drinking water has been associated with an array of adverse health effects including various cancers, vascular diseases, and neurologic effects. The primary aim of the current protocol is to determine the extent to which arsenic in the blood of a pregnant woman crosses the placenta and is present in the blood of the newborn child. This aim will be achieved through the measurement of total arsenic in maternal and umbilical cord pairs of blood samples. Arsenic is actually methylated (i.e. detoxified) by the human liver (to monomethyl and dimethylarsenic), and adults and children vary widely in their ability to carry out these reactions. Thus, a secondary aim of this project is to examine the extent to which mothers and newborn infants can methylate arsenic, and determine whether blood homocysteine, folate and vitamin B12 concentrations are related to arsenic methylation.The proposed study will recruit pregnant women in the third trimester of pregnancy among those who visit the Matlab hospital for their prenatal check up. We anticipate recruiting as many as 150 non-smoking women, ages 20 to 38, into the study, in order to obtain maternal-cord blood pairs at the time of delivery at the health centre. After ensuring their eligibility and informed consent, participants will be asked about their water source and use of any vitamins during pregnancy. Since the previous iteration of this protocol was approved 5 years ago by Columbia University the new modified version of the protocol has been submitted again to the IRB of Columbia University for approval. The proposed study of 150 women who have had a very wide range of arsenic exposure from drinking water will afford us an opportunity to definitively describe the maternal-cord blood arsenic relationship, and methylation of arsenic by pregnant women and neonates in relation to folate and vitamin B12 concentration in their blood. This information may be useful in taking appropriate measures to help reduce the harmful effects of arsenic exposure in pregnant women and neonates in Bangladesh and other countries of the world where environmental arsenic exposure is a problem.